Answer: I think your first contact should be the maintenance facility of the Parks & Recreation Department. Helpful folks there can work with you on the installation of your scout project:
Parks & Recreation
27801 La Paz Road
Laguna Niguel, CA 92677
I suspect there are city guidelines as to what can be installed in public places, as well as how to install your project so it meets the written standards.
If the soil is compacted (which I presume it is), all you need to do is dig down and remove about 6" of soil, level the area, install your wishing well and cover the bare ground with weed barrier fabric. Then spread about 4" of chipped granite or 1 to 1 1/2" rocks. I'd avoid using pea gravel because it seems to disappear in high traffic areas. For the barrier, you can find lengths of plastic barrier along with plastic stakes. These are usually soil in a long coil and you can pick up a few (depending upon desired length). They are easy to install. You just need to dig a trench, set the barrier in the trench and firm soil around it to hold it in place. Keep the barrier a couple of inches higher than the finished grade of the gravel to make sure the gravel isn't accidentally kicked out of the walkway.
I'm sure the above contact will provide lots of information for your scout project. Eagle Scouts are usually quite willing to help other scout groups with projects so you may enlist their aid, as well.
Best wishes with your project!
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